001/*
002 * Copyright 2002-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.web.client;
018
019import java.io.IOException;
020import java.nio.charset.Charset;
021
022import org.springframework.http.HttpHeaders;
023import org.springframework.http.HttpStatus;
024import org.springframework.http.MediaType;
025import org.springframework.http.client.ClientHttpResponse;
026import org.springframework.util.FileCopyUtils;
027
028/**
029 * Spring's default implementation of the {@link ResponseErrorHandler} interface.
030 *
031 * <p>This error handler checks for the status code on the {@link ClientHttpResponse}:
032 * Any code with series {@link org.springframework.http.HttpStatus.Series#CLIENT_ERROR}
033 * or {@link org.springframework.http.HttpStatus.Series#SERVER_ERROR} is considered to be
034 * an error; this behavior can be changed by overriding the {@link #hasError(HttpStatus)}
035 * method. Unknown status codes will be ignored by {@link #hasError(ClientHttpResponse)}.
036 *
037 * @author Arjen Poutsma
038 * @author Rossen Stoyanchev
039 * @author Juergen Hoeller
040 * @since 3.0
041 * @see RestTemplate#setErrorHandler
042 */
043public class DefaultResponseErrorHandler implements ResponseErrorHandler {
044
045        /**
046         * Delegates to {@link #hasError(HttpStatus)} (for a standard status enum value) or
047         * {@link #hasError(int)} (for an unknown status code) with the response status code.
048         * @see ClientHttpResponse#getRawStatusCode()
049         * @see #hasError(HttpStatus)
050         * @see #hasError(int)
051         */
052        @Override
053        public boolean hasError(ClientHttpResponse response) throws IOException {
054                int rawStatusCode = response.getRawStatusCode();
055                for (HttpStatus statusCode : HttpStatus.values()) {
056                        if (statusCode.value() == rawStatusCode) {
057                                return hasError(statusCode);
058                        }
059                }
060                return hasError(rawStatusCode);
061        }
062
063        /**
064         * Template method called from {@link #hasError(ClientHttpResponse)}.
065         * <p>The default implementation checks if the given status code is
066         * {@link HttpStatus.Series#CLIENT_ERROR CLIENT_ERROR} or
067         * {@link HttpStatus.Series#SERVER_ERROR SERVER_ERROR}.
068         * Can be overridden in subclasses.
069         * @param statusCode the HTTP status code as enum value
070         * @return {@code true} if the response indicates an error; {@code false} otherwise
071         * @see HttpStatus#is4xxClientError()
072         * @see HttpStatus#is5xxServerError()
073         */
074        protected boolean hasError(HttpStatus statusCode) {
075                return (statusCode.is4xxClientError() || statusCode.is5xxServerError());
076        }
077
078        /**
079         * Template method called from {@link #hasError(ClientHttpResponse)}.
080         * <p>The default implementation checks if the given status code is
081         * {@code HttpStatus.Series#CLIENT_ERROR CLIENT_ERROR} or
082         * {@code HttpStatus.Series#SERVER_ERROR SERVER_ERROR}.
083         * Can be overridden in subclasses.
084         * @param unknownStatusCode the HTTP status code as raw value
085         * @return {@code true} if the response indicates an error; {@code false} otherwise
086         * @since 4.3.21
087         * @see HttpStatus.Series#CLIENT_ERROR
088         * @see HttpStatus.Series#SERVER_ERROR
089         */
090        protected boolean hasError(int unknownStatusCode) {
091                int seriesCode = unknownStatusCode / 100;
092                return (seriesCode == HttpStatus.Series.CLIENT_ERROR.value() ||
093                                seriesCode == HttpStatus.Series.SERVER_ERROR.value());
094        }
095
096        /**
097         * This default implementation throws a {@link HttpClientErrorException} if the response status code
098         * is {@link org.springframework.http.HttpStatus.Series#CLIENT_ERROR}, a {@link HttpServerErrorException}
099         * if it is {@link org.springframework.http.HttpStatus.Series#SERVER_ERROR},
100         * and a {@link RestClientException} in other cases.
101         */
102        @Override
103        public void handleError(ClientHttpResponse response) throws IOException {
104                HttpStatus statusCode = getHttpStatusCode(response);
105                switch (statusCode.series()) {
106                        case CLIENT_ERROR:
107                                throw new HttpClientErrorException(statusCode, response.getStatusText(),
108                                                response.getHeaders(), getResponseBody(response), getCharset(response));
109                        case SERVER_ERROR:
110                                throw new HttpServerErrorException(statusCode, response.getStatusText(),
111                                                response.getHeaders(), getResponseBody(response), getCharset(response));
112                        default:
113                                throw new UnknownHttpStatusCodeException(statusCode.value(), response.getStatusText(),
114                                                response.getHeaders(), getResponseBody(response), getCharset(response));
115                }
116        }
117
118        /**
119         * Determine the HTTP status of the given response.
120         * <p>Note: Only called from {@link #handleError}, not from {@link #hasError}.
121         * @param response the response to inspect
122         * @return the associated HTTP status
123         * @throws IOException in case of I/O errors
124         * @throws UnknownHttpStatusCodeException in case of an unknown status code
125         * that cannot be represented with the {@link HttpStatus} enum
126         * @since 4.3.8
127         */
128        protected HttpStatus getHttpStatusCode(ClientHttpResponse response) throws IOException {
129                try {
130                        return response.getStatusCode();
131                }
132                catch (IllegalArgumentException ex) {
133                        throw new UnknownHttpStatusCodeException(response.getRawStatusCode(), response.getStatusText(),
134                                        response.getHeaders(), getResponseBody(response), getCharset(response));
135                }
136        }
137
138        /**
139         * Read the body of the given response (for inclusion in a status exception).
140         * @param response the response to inspect
141         * @return the response body as a byte array,
142         * or an empty byte array if the body could not be read
143         * @since 4.3.8
144         */
145        protected byte[] getResponseBody(ClientHttpResponse response) {
146                try {
147                        return FileCopyUtils.copyToByteArray(response.getBody());
148                }
149                catch (IOException ex) {
150                        // ignore
151                }
152                return new byte[0];
153        }
154
155        /**
156         * Determine the charset of the response (for inclusion in a status exception).
157         * @param response the response to inspect
158         * @return the associated charset, or {@code null} if none
159         * @since 4.3.8
160         */
161        protected Charset getCharset(ClientHttpResponse response) {
162                HttpHeaders headers = response.getHeaders();
163                MediaType contentType = headers.getContentType();
164                return (contentType != null ? contentType.getCharset() : null);
165        }
166
167}